SharePoint 2013 includes improved enterprise search, document sharing and collaboration, social networking enhancements, and a new development framework for ISVs.
Windows Server 2012 R2 includes numerous new or improved storage, manageability, identity and virtualization features that may make it a compelling upgrade for enterprises.
Organizations that chose to skip evaluating Windows 8 may find that both Windows 8.1 (and Windows RT 8.1) now have enterprise-focused features that warrant review.
The redesigned Product List should allow customers and partners to answer some licensing questions faster and might be less intimidating to first-time users
Rule changes for licensing SQL Server under the Server + CAL model, which generally requires licenses for all servers running SQL Server in production and all clients accessing the servers, may complicate license compliance
When deploying third party server-based desktop solutions such as Citrix XenDesktop, any Microsoft software used in the infrastructure must be licensed correctly